Not a mommy yet, im only 23...but while i was in nursing school
i babysat for a single mom. She had about 3-4 babysitters she would rely on. she worked nights, so we all loved babysitting her kids. I picked the kids up from school so she could sleep before she goes to work. She woke up enough time to have dinner with the kids. She would leave, i would get the kids ready for bed, finish up homework if we needed more time etc.
they go off to bed at 8:00 on weekdays, 9:00 on weekend and i get the house quiet, time for me to study and do my homework.
She had a bedroom for her babysitters. I'd get the kids up/ready for school, she would come home have breakfast with the kids and the kids would be off to school, she would sleep...and to do it all over again.
So yea...not a mommy, but i know it can be done. I know single moms who still work as a nurse, some how they manage to work and raise wonderful children